1. Field
One or more embodiments described herein relate to a rechargeable battery.
2. Description of the Related Art
Rechargeable batteries are used in a variety of applications. A low-capacity rechargeable battery is used in small portable electronic devices such as mobile phones, notebook computers, and camcorders. A high-capacity rechargeable battery is used for driving the motor of a hybrid vehicle.
A rechargeable battery generally includes an electrode assembly having a positive electrode and a negative electrode at opposite surfaces of a separator. The electrode assembly is include din a case, and a cap plate is used to seal an opening of the case. Positive and negative electrode terminals penetrate the cap plate for electrical coupling to the electrode assembly. In one instance, the positive electrode terminal may be electrically coupled to the cap plate to positively charge the cap plate and the case.
When a conductor (e.g., a nail) penetrates the case and pierces the electrode assembly, high voltage current flowing through the positive electrode terminal may flow back to the electrode assembly by way of the cap plate, the case, and the conductor.
In order to protect against damage from penetration of the conductor, a short-circuit member may positioned be between the electrode assembly and the case, and may be negatively charged. When the conductor penetrates the positively charged case, the conductor contacts the negatively charged short-circuit member and current charged in the electrode assembly discharges through the conductor from the case and the short-circuit member, to thereby prevent ignition or explosion of the electrode assembly.
When the conductor penetrates the case and pierces the short-circuit member, the conductor forms a path through which the current flows out of the electrode assembly, to thereby allow a limited amount of current to be controlled. In addition, the current flowing out of the electrode assembly may be introduced into the conductor via the positive electrode terminal, the cap plate, and the case, and may cause secondary damage to the electrode assembly. In this case, the positive electrode terminal makes surface contact with the cap plate, and thereby is unable to control the amount of current.